package me.gavincook.mybatis.plugins;

import java.util.List;

import org.mybatis.generator.api.CommentGenerator;
import org.mybatis.generator.api.IntrospectedTable;
import org.mybatis.generator.api.PluginAdapter;
import org.mybatis.generator.api.dom.java.Field;
import org.mybatis.generator.api.dom.java.FullyQualifiedJavaType;
import org.mybatis.generator.api.dom.java.JavaVisibility;
import org.mybatis.generator.api.dom.java.Method;
import org.mybatis.generator.api.dom.java.Parameter;
import org.mybatis.generator.api.dom.java.TopLevelClass;
import org.mybatis.generator.api.dom.xml.Attribute;
import org.mybatis.generator.api.dom.xml.TextElement;
import org.mybatis.generator.api.dom.xml.XmlElement;

/**
 * 分页插件
 *
 * @author gavincook
 * @version $ID: PaginationPlugin.java, v0.1 2018-01-08 11:48 gavincook Exp $$
 */
public class PaginationPlugin extends PluginAdapter {

    private String pageSize;

    @Override
    public boolean validate(List<String> warnings) {
        return true;
    }

    @Override
    public boolean modelExampleClassGenerated(TopLevelClass topLevelClass, IntrospectedTable introspectedTable) {
        this.pageSize = properties.getProperty("pageSize", "15");
        addFileAndGetterSetterForInteger(topLevelClass, introspectedTable, "offset", "0");
        addFileAndGetterSetterForInteger(topLevelClass, introspectedTable, "limit", pageSize );
        return super.modelExampleClassGenerated(topLevelClass, introspectedTable);
    }

    @Override
    public boolean sqlMapSelectByExampleWithoutBLOBsElementGenerated(XmlElement element,
                                                                     IntrospectedTable introspectedTable) {
        XmlElement isNotNullElement = new XmlElement("if");
        isNotNullElement.addAttribute(new Attribute("test", "offset != null and offset >=0"));
        isNotNullElement.addElement(new TextElement("limit ${offset} , ${limit}"));
        element.addElement(isNotNullElement);

        return super.sqlMapSelectByExampleWithoutBLOBsElementGenerated(element, introspectedTable);
    }

    @Override
    public boolean sqlMapSelectByExampleWithBLOBsElementGenerated(XmlElement element, IntrospectedTable introspectedTable) {
        XmlElement isNotNullElement = new XmlElement("if");
        isNotNullElement.addAttribute(new Attribute("test", "offset != null and offset >=0"));
        isNotNullElement.addElement(new TextElement("limit ${offset} , ${limit}"));
        element.addElement(isNotNullElement);

        return super.sqlMapSelectByExampleWithBLOBsElementGenerated(element, introspectedTable);
    }

    /**
     * 增加字段，并添加getter/setter
     * @param topLevelClass
     * @param introspectedTable
     * @param name
     */
    private void addFileAndGetterSetterForInteger(TopLevelClass topLevelClass, IntrospectedTable introspectedTable,
                                                  String name, String defaultValue) {

        CommentGenerator commentGenerator = context.getCommentGenerator();
        Field field = new Field();
        field.setVisibility(JavaVisibility.PROTECTED);
        field.setType(FullyQualifiedJavaType.getIntInstance());
        field.setName(name);
        field.setInitializationString(defaultValue);
        commentGenerator.addFieldComment(field, introspectedTable);
        topLevelClass.addField(field);

        char c = name.charAt(0);
        String camel = Character.toUpperCase(c) + name.substring(1);

        Method method = new Method();
        method.setVisibility(JavaVisibility.PUBLIC);
        method.setName("set" + camel);
        method.addParameter(new Parameter(FullyQualifiedJavaType.getIntInstance(), name));
        method.addBodyLine("this." + name + "=" + name + ";");
        commentGenerator.addGeneralMethodComment(method, introspectedTable);
        topLevelClass.addMethod(method);

        method = new Method();
        method.setVisibility(JavaVisibility.PUBLIC);
        method.setReturnType(FullyQualifiedJavaType.getIntInstance());
        method.setName("get" + camel);
        method.addBodyLine("return " + name + ";");

        commentGenerator.addGeneralMethodComment(method, introspectedTable);
        topLevelClass.addMethod(method);
    }
}
